As known to those skilled in the art, a pantyhose article provided with a gusset is obtained starting from a product obtained by assembling two stockings sewn together to form the pantyhose bodice and without sewing them in correspondence of the crotch region. Provision is made afterwards for stretching the edge of the seamless region of said article according to the shape of the gusset to be applied, bringing close thereto a gusset having a shape and dimensions suitable for covering the region without fabric of the thus stretched article, and eventually sewing the gusset to the article which is subsequently unloaded at an operating station other than that for applying and sewing the gusset. To this end, a device for the application of the gussets is associated to the machine that provides for the assembly of the stockings, said device being provided at an operating station downstream of the stations in which the loading, positioning, longitudinal cutting and sewing together of the two stockings intended to form the pantyhose article are carried out.
The devices presently known for gusset application, especially those intended for applying rhomboid gussets, comprise means for feeding a fabric ribbon from which the gussets are formed, means for cutting the ribbon into rhomboid gussets, the cut being oriented with respect to the longitudinal axis so as to form an angle therewith of a predetermined amplitude corresponding to the wanted length of the rhombus diagonals, and means for taking out the thus formed gussets and moving them from the gusset-forming region to the region where the same gussets are applied on the stockings to be assembled.
A drawback with these known devices lies in the fact that the formation of a gusset out of the said ribbon is possible only after the application of the gusset previously formed. In other words, each gusset can be formed only after the previous gusset has been transferred in correspondence of the shapes of the machine that assembles the stockings into pantyhose articles. As a consequence, the time of the cycle for the formation and application of the gussets results too long in relation to the current production requirements.
U.S. Pat. Nos. 4,704,976 and 4,640,162 disclose an apparatus and a method for the formation and application of rhomboid gussets on stockings to be assemble into pantyhose articles.